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  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
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  <script>
    /* // 更新变量
    let age = 18
    age = 19 */

    // 声明多个变量(不建议)
    let age = 18, uname = 'pink'
    console.log(age,uname)
    
  </script>
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